1. Field of the Invention
The present invention relates to an inkjet recording apparatus and an inkjet recording method, and particularly relates to an inkjet recording apparatus and an inkjet recording method capable of stably carrying out back pressure control in which back pressure is applied to a liquid inside a nozzle of an inkjet recording head.
2. Description of the Related Art
Japanese Patent Application Publication No. 2007-245568 discloses that a recording head is provided with a pressure regulating chamber container that regulates pressure inside a sub-tank of the recording head, and is further provided with an elastic deformation member for regulating a pressure of a gas inside this pressure regulating chamber container, and forming an indentation or a flat surface for example in a portion of the elastic deformation member enables deformation to be caused from a specific location so as to stabilize a negative pressure characteristic of the pressure regulating chamber.
However, it is necessary to devise a shape of the elastic deformation member, and unevenness in dimensional accuracy during production of the elastic deformation member may occur easily, which makes it difficult to control the modulus of elasticity. Therefore there is a risk that it may not be possible to stabilize the negative pressure characteristics of the pressure regulating chamber.
Moreover, compactness is difficult to achieve since it is necessary to arrange the elastic deformation member directly above the recording head. Furthermore, since the pressure of the gas inside the pressure regulating chamber container is regulated by causing deformation of the elastic deformation member from a specific location, there is a risk that the durability of the elastic deformation member is reduced.
Japanese Patent Application Publication No. 2007-245452 discloses that in back pressure control of a recording head, by supplying and discharging ink between an inside of a tightly sealable intermediate tank and an ink tank, the pressure of a gas inside the intermediate tank is controlled, thereby ensuring a uniform negative pressure inside the nozzles of the recording head.
However, since the ink and the gas are in direct contact inside the intermediate tank, an ink degassing effect cannot be maintained and there is a risk that the ejection characteristics of the recording head will deteriorate. Furthermore, since no damping function is provided to damp pressure fluctuations in the ink when pressure fluctuations of the gas inside the intermediate tank are transmitted to the ink, time is required for the pressure fluctuations of the ink to settle, and there is a risk that back pressure control of the recording head is not stable.